fixed; aggregation exec w/o callback

now returns a promise
fixed; aggregation exec w/o model

now returns a promise
tests; fixes for legacy node version
tests; longer timeout for geoNear tests
fixed; geoNear: guarantee async semantics

callback must fire on next tick at the earliest.
tests; changes for joyent
tests; add check for 2.4 on geoNear
update history
only markModified if subtype changed
release 3.7.0
website; tweak homepage
docs; make docs updates
website; add 3.7 release notes
now working on 3.7.1